Leptospirosis’s abrupt resurgence: types, bacteriology, molecular genetics, etiology, diagnostic testing, transmission, symptoms, and medications
Authors: Md. Mominur Rahman, Md. Rezaul Islam, Puja S. Dhar
Journal: International Journal of Surgery (2023)

Dear Editor, Both humans and animals can contract the bacterial infection known as leptospirosis. Leptospira bacteria play a role in their emergence. Many different symptoms may be experienced by people who have it, some of which may be confused for those of other conditions. In addition, not all infected people will experience symptoms. Leptospirosis can cause death if left untreated because it can cause kidney damage, meningitis (an infection of the membrane around the brain and spinal cord), liver failure, and breathing issues1. United Republic of Tanzania’s Ministry of Health alerted WHO on 14 July 2022, to 13 instances of an unidentified illness that was later determined to be leptospirosis. On July 5 and 7, the first two cases arrived at a health center in Ruangwa District, Lindi Region, with symptoms including fever, nosebleeds, headaches, and generalized weakness. In the end, samples tested positive for leptospirosis at the Sokoine University of Agriculture reference laboratory despite testing negative for Rift Valley fever, Crimean-Congo hemorrhagic fever, Yellow fever, Chikungunya, and Ebola virus disease at the National Public Health Laboratory and the Tanzania Veterinary Laboratory Agency. Twenty leptospirosis cases and three fatalities had been reported as of August 8 from two districts in the Lindi Region, including Ruangwa (18 cases) and Kilwa (2 cases). Laboratory confirmation of 15 of these cases has shown one death (case fatality rate: 6.7%). Of the remaining five instances, samples were not obtained in two cases, one of which resulted in death, and three cases, including one fatality, tested negative for leptospirosis. The cases ranged in age from 18 to 77 (median age: 45), with the bulk (n=15; 75%) falling between the ages of 31 and 60. Males who were farmers by profession and were found in a temporary camp for agricultural activities made up the majority of the instances (n=15, 75%). During active case finding, those who reported the beginning of symptoms between June 30 and July 3 were located in the neighborhood. Most individuals reported symptoms beginning between July 2 and July 6, and the most recent instances reported symptoms beginning on July 7. Since July 15th, there have been no further cases reported. To find any new or overlooked cases, active case finding and field investigations are still being conducted2. Leptospirosis can occur in one of two different phases or forms: (1) Anicteric syndrome: The initial stage of leptospirosis is an anicteric syndrome. Overall, 90% of cases are due to a minor sickness that resembles the flu. (2) Icteric syndrome: If a person recovers but then becomes ill once more, leptospirosis will progress to its second stage. Icteric syndrome or Weil’s illness is the name of this variation. It is more serious. This kind of leptospirosis typically lasts for several weeks. Compared with the initial stage of leptospirosis, it is less frequent3. Leptospires are members of the family Leptospiraceae, genus Leptospira, and order Spirochaetales. They may be saprophytic or pathogenic. In much different damp or humid conditions, pathogenic leptospires can be sustained naturally in the renal tubules of animals and saprophytic leptospires4. Leptospires and other spirochetes have phylogenetic relationships. A 5000 kbp is roughly the size of the leptospiral genome, while lesser estimations have been recorded. A 4400 kbp chromosome and a smaller 350 kbp chromosome make up the genome’s two parts. Unreported plasmids include others. From serovars of the pomona subtype Kennewick and icterohaemorrhagiae, physical maps have been created. The rRNA genes are widely spread, and leptospires have two sets of 16S and 23S rRNA genes but only one 5S rRNA gene. The absence of a transformation system has delayed down research on leptospiral genetics. A shuttle vector was recently created utilizing the Leptospira biflexa temperate bacteriophage LE1. With this development, it may be possible to understand Leptospira at the molecular level more quickly5. The bacteria called Leptospira interrogans is the source of leptospirosis. Numerous animals carry the germs, which are found in their kidneys, around. The land and water are contaminated by their urine. If you come into contact with water or dirt where an infected animal has urinated, the germ might enter your body through dry areas, scratches, or open sores in your skin. The mouth, genitalia, and nose are other possible entry points. Although human papillomavirus can be contracted from another person, it is most commonly spread through sex or breastfeeding. Your safety is in jeopardy if you spend a lot of time outside or with animals. If you are employed as an agricultural worker, veterinary technician, underground worker (in a mine or sewer), or slaughterhouse worker. In addition, the disease may be contracted if you camp, swim, or float close to infected lakes and rivers. Warm climates are where leptospirosis is more prevalent. Despite being widespread around the world, the bacteria is most common in Africa, Australia, Southeast Asia, South and Central America, and the Caribbean6. Four major clinical subtypes of the disease are frequently present: The most typical ailments include a mild influenza-like illness, Weil syndrome, meningitis/meningoencephalitis, pulmonary hemorrhage with respiratory failure, and a moderate influenza-like illness. In addition to a wide range of symptoms and signs, leptospirosis is most frequently characterized clinically by headache, fever, myalgia (especially in the calf muscle), jaundice, general malaise, and conjunctival suffusion. Incubation lasts for 4–13 days, ranging from 3 to 30 days. There are times when the sickness’ symptoms are mistaken for those of dengue and other hemorrhagic fevers, both of which are widespread in the tropics. Animal disease exposure in the past or having spent time in an environment that might have been contaminated with animal urine while working or having fun7. It is possible for humans to become directly infected by diseased animals (via contact with milk, urine, vaginal discharge, aborted fetuses, and placenta), as well as indirectly (by contact with contaminated water and soil). There are three ways in which bacteria from sick animals or the environment might enter the body: (1) Direct contact: Bacteria enter the body through breaks in the skin’s outer layer or healthy mucous membranes, such as an open wound that is exposed to contaminated water or debris. (2) Eating or drinking: for instance, ingesting contaminated food or using unclean hands that are infected with microorganisms. (3) Inhalation, such as taking in aerosolized urine from infected rats or mice or cattle. Although it is uncommon, person-to-person transmission has been linked to nursing and sexual activity in the past. Humans may experience repeated illnesses as a result of recurrent infections with various bacterial strains8. After a 2- to 20-day incubation period, symptoms frequently appear suddenly. The acute phase is characterized by direct tissue damage caused by leptospire invasion and toxins, which have been hypothesized but never definitively proven. After the systemic multiplication of leptospires stops, symptoms go away. The second stage, sometimes referred to as the immunological phase, is marked by increased antibody titers and an inflammatory infiltration of the damaged organ systems. The immunological phase is characterized by renal failure and aseptic meningitis. With a mean length of 14 days, symptoms may last anywhere from 6 days to more than 4 weeks. Leptospirosis diagnoses are associated with Weil disease in about 10% of individuals. Weil illness is typically described as severe leptospirosis that manifests as jaundice, renal failure, and pulmonary bleeding. Significantly with care in an ICU, mortality rates for these patients are 10%, and they are even higher in areas with less advanced medical facilities. Leptospirosis infections that are deadly or severe may not have any accompanying jaundice. Leptospirosis commonly manifests as fever, myalgia, and headache in both children and adults. Fatigue, cough, emesis, stomach cramps, photophobia, arthralgia, constipation, or diarrhea are additional potential symptoms. These symptoms have a complicated differential diagnosis that ranges from meningitis and sepsis to benign viral pediatric diseases9. These are administered in the management of leptospirosis, including (1) Antibiotics: Doxycycline, amoxicillin, ampicillin, penicillin-G, and ceftriaxone are some of the antibiotics that can be used to treat leptospirosis. Depending on how will you are and your medical history, your provider will pick which to employ. (2) Mechanical ventilation: If your lungs are contaminated with bacteria, it’s possible that you’ll have trouble breathing and require the assistance of a machine. To help you sleep while you are attached to the machine, your doctor will prescribe you sleeping pills. (3) Plasmapheresis, also known as plasma exchange, may be beneficial for those who are susceptible to organ damage from leptospirosis. Your healthcare professional uses a tube connected to a vein to draw blood during this treatment. Your plasma is removed from your blood by a machine, and a plasma substitute is then used in its place. A different tube is then used to return your blood to your body10. So, the pivotal aim of this study was to discuss outbreak, types, bacteriology, molecular genetic features, etiology, diagnosis, transmission, sign, symptoms, and medications of leptospirosis. Ethics approval Not applicable. Sources of funding Not applicable. Authors’ contribution M.M.R.: conceptualization, writing—original draft preparation and supervision. M.R.I. and P.S.D.: writing, editing. Conflicts of interest disclosure The authors declare that they have no financial conflict of interest with regard to the content of this report. Research registration Unique Identifying number (UIN) None. Guarantor Md. Mominur Rahman. Data availability statement All data used to support the findings of this study are included in the article.